Iím new here found this site tonight by surfing the net trying to learn more on inductor coils. I have a friend thatís trying to help me tune my speakers in my home I have built a couple of years ago. Just to give you an idea of what I have which weíre trying to tune is a set of custom built Dynaudio speakers 66Ē weighing close to 500lbs. It has the DíAppolito designed configuration with the two 30W100 woofers, two 17W75LQ mids and the Esotar tweeter set up for bi-wiring, being driven with a Krell KSA300S through a Klyne System 7 preamp which Iím hoping to replace soon with a Krell preamp. Ever since moving into my dedicated room which measures 28íX 16í I have lost some bass from these speakers. What Iím looking for is more gain on the lower end. I have talked to the speaker designer that built this pair which was tuned for my previous home whrer the room was much smaller. He said what he was going to do was to take out my Solen 4mh air core inductor coil and replace it a steel laminate inductor coil with less resistant. I have been out of it for a while and Iím just getting back into the hobby. What brand of coils now these days are the best of the best on the market at a no cost factor that would be low resistant that you may know of that you can recommend. Also has anyone heard of Goertz brand of air core foil inductors? Iím open to suggestions and my main issue is trying to get the lower end back. Any info would be appreciated.

Martin King (MJK on this forum, probably frostbit in upstate NY and unable to move his fingers about the keyboard) has done a lot of work with MathCAD allowing you to play around with values and derive an optimal box situation. Just using the stock values for one of his sytems we can illustrate the effect of inserting series resistance into the system -- the first chart has zero inserted resistance, the second has 2 ohms :

Iím new here found this site tonight by surfing the net trying to learn more on inductor coils. I have a friend thatís trying to help me tune my speakers in my home I have built a couple of years ago. Just to give you an idea of what I have which weíre trying to tune is a set of custom built Dynaudio speakers 66Ē weighing close to 500lbs. It has the DíAppolito designed configuration with the two 30W100 woofers, two 17W75LQ mids and the Esotar tweeter set up for bi-wiring, being driven with a Krell KSA300S through a Klyne System 7 preamp which Iím hoping to replace soon with a Krell preamp. Ever since moving into my dedicated room which measures 28íX 16í I have lost some bass from these speakers. What Iím looking for is more gain on the lower end. I have talked to the speaker designer that built this pair which was tuned for my previous home whrer the room was much smaller. He said what he was going to do was to take out my Solen 4mh air core inductor coil and replace it a steel laminate inductor coil with less resistant. I have been out of it for a while and Iím just getting back into the hobby. What brand of coils now these days are the best of the best on the market at a no cost factor that would be low resistant that you may know of that you can recommend. Also has anyone heard of Goertz brand of air core foil inductors? Iím open to suggestions and my main issue is trying to get the lower end back. Any info would be appreciated.